MADISON, Wis. - The city of Madison grants more than a million dollars each year to organizations helping the area's homeless community, but officials don't do annual audits to determine if criminal background checks are being done on the people who are volunteering with those groups.

News 3 Investigates began looking into the issue after Kristine Pierstorff and another woman who has requested anonymity, both homeless, claimed they'd been sexually assaulted by one of the volunteers at Sanctuary Storage. The organization runs a space where homeless individuals can store their belongings. Neither woman filed a report with the Madison Police Department and no one has been charged as a result. The volunteer who they allege assaulted them is a registered sex offender with multiple past convictions and who is facing new charges for allegedly exposing himself at a Madison department store.

"I think there are people with certain backgrounds who should really not be allowed around vulnerable populations like this," Pierstorff said. "You've got people with disabilities here, mental and physical disabilities that may make them less likely to be able to handle a situation like that."

Madison's standard contract with Sanctuary Storage and all of its grantees clearly states that the organization assumes the responsibility to "use reasonable application and screening tools to select employees and volunteers who work directly with vulnerable clients," including but not limited to "criminal background checks." The head of Sanctuary Storage did not respond to News 3's multiple requests for comment, but city officials say he acknowledged criminal background checks were not done on his volunteers.

"I think the city has a responsibility to make sure that everything possible is done to provide for the safety of the people we're trying to serve," said Jim O'Keefe, who runs Madison's Community Development Division. "It would have made sense for volunteers involved in the operation of the storage center to have had background checks conducted. We are now committed to doing that."

O'Keefe said oversight of his division's contracts are usually "complaint based," and that grantees "don't have to routinely prove they're meeting every contract requirement," including background checks. He said he believes the lack of checks at Sanctuary Storage is not likely an isolated incident.

"I can't think of another example, but frankly, I don't have much doubt that there have been others," he said.

Pierstorff said the volunteer groped and grabbed her when she and her fiancé got a hotel room earlier this year to shower and clean up. The other homeless woman alleges she was sexually assaulted in a side room of Sanctuary Storage that had been outfitted with a bed.

"The claims from the victims are heartbreaking," wrote Matt Kozlowski, who is the chairman of the board of the Social Justice Center, which owns the building where Sanctuary Storage is located. "We were unaware of any such activity in our building. Our hearts go out to the victims and we'll be keeping (them) in our thoughts."

Kozlowski said at the board's last meeting, members agreed the center's present arrangement with Sanctuary Storage isn't working and that if another lease were to be signed past its current term of Dec. 31, then changes would need to be made. He said the board remained committed to the service being provided. The city has paid $65,000 in rent for the Sanctuary Storage facility in the last three years.

Pierstorff now believes she should have filed a report with the police, as her fiancé had advised after the incident happened. Her big fear is what happens now to a facility that provides the city's homeless community the only place to store their belongings if they have a job interview or other appointment.

"I obviously don't want to lose the service, it's too important," she said. "I just think there should be some caution and some discretion on who they allow to volunteer."

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